Diazo negative color proofing process utilizing acrylic/acrylate polymers

ABSTRACT

The invention relates to negative photosensitized sheet constructions which, upon exposure to an actinic radiation source through a screened image, can accurately reproduce said image. The construction is useful as a color proofing film which can be employed to predict the image quality from a lithographic printing process.

This application is a continuation of application Ser. No. 06/909,138,filed Sept. 19, 1986, abandoned, which is a continuation-in-part of U.S.Pat. application Ser. No. 880,770 filed July 1, 1986 now abandoned.

BACKGROUND OF THE INVENTION

In the graphic arts, it is desirable to produce a color proof to assista printer in correcting a set of photomasks which will be used inexposing printing plates. The proof should reproduce the color qualitythat will be obtained during the printing process. The proof must be aconsistent duplicate of the desired half tone or line image, and shouldneither gain nor lose color. Visual examination of a color proof shouldreveal the following characteristics:

1. Any defects on the photomask.

2. The best color rendition to be expected from press printing of thematerial.

3. The correct gradation of all colors and whether grays are neutral.

4. The need, if any, for subduing any of the colors and/or givingdirections for altering the film photomask before making the printingplates.

Color proofing sheets for multi-colored printing have heretofore beenmade by using a printing press proof which requires taking all the stepsnecessary for actual multicolor printing. Such a conventional method ofcolor proofing has been costly and time consuming. Alternate colorproofing methods have therefore been developed to simulate the qualityof press proofs. There are two known types of photographic colorproofing methods, namely, the surprint type and the overlay type.

In the overlay type of color proofing, an independent transparentplastic support is used for producing an image of each color separationfilm. A number of such supports carrying colored images are thensuperimposed upon each other and placed on a white sheet to produce acolor proof. The overlay type of color proofing method has thedisadvantage that the superimposed plastic supports tend to darken thecolor proofing sheet, and, as a result, the impression of the colorproofing sheet thus prepared becomes vastly different from copiesactually obtained by a conventional printing press proof. Its primaryadvantage is that it is quick and can serve as a progressive proof bycombining any two or more colors in register.

In the surprint type of color proofing method, a color proofing sheet isprepared by successively producing images of different colors fromdifferent color separation films onto a single receptor sheet. This isdone by utilizing a single opaque support and by applying toners,photosensitive solutions or coatings of photosensitive materials ofcorresponding colors on the opaque support in succession. An example ofthis approach is described in U.S. Pat. No. 3,671,236. An advantage ofthe surprint type of color proof is that the color saturation is notinfluenced by superimposed plastic supports. This method more closelyresembles the actual printing and eliminates the color distortioninherent in the overlay system.

Various processes for producing copies of an image embodyingphotopolymerization and thermal transfer techniques are known as shownin U.S. Pat. Nos. 3,060,023; 3,060,024; 3,060,025 3,481,736; and3,607,264. In these processes, a photopolymerizable layer coated on asuitable support is imagewise exposed to a photographic transparency.The surface of the exposed layer is then pressed into contact with theimage receptive surface of a separate element and at least one of theelements is heated to a temperature above the transfer temperature ofthe unexposed portions of the layer. The two elements are thenseparated, whereby the thermally transferrable, unexposed, image areasof the composite transfer to the image receptive element. If the elementis not precolored, the tacky unexposed image may now be selectivelycolored with a desired toner. The colored matter preferentially adheresto the clear unpolymerized material. U.S. Pat. No. 3,574,049 provides atransfer process for printing a design on a final support whichcomprises (a) printing a design onto a temporary support, (b)superimposing the temporary support and the final support, (c) applyingheat and/or pressure to the superimposed structure formed in (b), and(d) separating the temporary support from the final support whichretains the printed design. The affinity of the design for the temporarysupport is lower than its affinity for the final support.

In U.S. Pat. No. 3,721,557 a method of transferring colored images isclaimed which provides a stripping layer coated between thephotosensitive element and the support. When the photosensitive layer isexposed to actinic light and developed, the more soluble portions areselectively removed to produce a visible image. The image-carryingsupport is pressed against a suitable adhesive coated receptor memberand, subsequently, the carrier support sheet is stripped to accomplishthe transfer of the image. A fresh layer of adhesive is applied to thereceptor for each subsequent transfer.

This invention presents an improvement over other proofing systems whichare susceptible to various deficiencies due to the considerabledisparity in physical properties between the polymers used in the colorand adhesive layers. Examples of this disparity include the glasstransition temperature, the coefficient of linear expansion, and thepercent elongation. Among the deficiencies resulting from the dissimilarphysical properties are "pullout voids" on lamination, occasionalincomplete solubility in the developer caused by disruption of thecolor/adhesive interface, and fracturing and distortion of color imagesupon storage, particularly at elevated temperatures.

Pullout voids occur when particles of dust, dirt, or other contaminantslie on the receiver base surface. Upon lamination the adhesive flows andconforms itself about the particle while the brittle color layer isunable to do so and fractures at the point of highest stress. Thefracture propagates through the adhesive layer causing a section of thetransfer film to remain untransferred on the temporary carrier afterlamination. By altering the tensile properties of the color layer suchthat it is no longer brittle, pullout voids are significantly reducedand dirt/dust contamination becomes less of a concern.

The phenomenon of incomplete development is most often observed when thelaminate composite is bent or flexed while still hot from the laminationprocess, especially as it exits from the laminator nip. In this manner astress is applied to the color and adhesive layers, the adhesive is ableto elongate in the direction of the stress to relieve the pressure,while the color layer cannot do so and develops micro-fractures intowhich the hot, flowing adhesive may diffuse. This essentially causes a"mixing" of the two layers at their interface. Mixing of the adhesiveinto the color layer reduces the solubility of the color layer indeveloper. In this manner areas of incomplete development areencountered which may again be averted by increasing the ability of thecolor layer to accommodate the stress.

Color layers produced using the polymers of this invention do notsubstantially fracture or distort upon extended storage at room orelevated temperatures.

The invention uses a photosensitive layer containing a resinous bindercomposition, which composition contains primarily an acrylicacid/acrylate copolymer characterized by a high tensile strength andpercent elongation. These may be optionally admixed with polymersselected from polyvinyl acetals, styrene-maleic anhydrides, and thepolyvinyl alcohol/polyvinyl acetate/polyvinyl acetal copolymers whichare described more fully in U.S. Pat. application Ser. No. 762,089 whichis incorporated herein by reference.

SUMMARY OF THE INVENTION

The present invention provides an improved method for forming a coloredimage which comprises:

(A.) providing a photosensitive element which comprises, in order:

(i) a substrate having a release surface; and

(ii) a single photosensitive layer on said release surface, whichphotosensitive layer comprises a light sensitive, negative working,polymeric diazonium compound; a resinous binder composition, whichcomposition contains a major amount of an acid containing acryliccopolymer having the formula ##STR1## wherein: R₁ is H or, CH₃

R₂ is CH₃, CH₂ CH₃, (CH₂)₃ CH₃, n-octyl, or 2-ethyl hexyl

R₃ is H, CH₃ or COOH

o is equal to 4 to 12, and

p is equal to 1, and

said copolymer having an average molecular weight in the range of fromabout 10,000 to about 300,000, and at least one colorant; and

(iii) an adhesive layer directly adhered to said color photosensitivelayer, which adhesive layer comprises a polyvinyl acetate polymer andwhich adhesive layer has a softening point in the range of from about60° C. to about 180° C.; and thereafter

(B.) either

(i) laminating said element with heat and pressure via said adhesivelayer to a developer resistant receiver sheet; and removing saidsubstrate by the application of peeling forces; and imagewise exposingsaid photosensitive layer to actinic radiation; or

(ii) imagewise exposing said photosensitive layer to actinic radiation;and laminating said element with heat and pressure via said adhesivelayer to a developer resistant receiver sheet; and removing saidsubstrate by the application of peeling forces; or

(iii) laminating said element with heat and pressure via said adhesivelayer to a developer resistant receiver sheet; and imagewise exposingsaid photosensitive layer to actinic radiation; and removing saidsubstrate by the application of peeling forces; and

(C.) removing the non-exposed areas of said photosensitive layer with asuitable liquid developer, which removing is conducted at a temperatureat which said adhesive layer is substantially non-tacky; and preferably

(D.) repeating steps A through C at least once whereby anotherphotosensitive element having at least one different colorant islaminated onto said receptor sheet over the non-removed portions of thepreviously laminated photosensitive layer or layers.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In carrying out the method of the invention, one employs a photographicelement which broadly comprises a substrate having a release surface, acolored photosensitive layer on the release surface and an adhesivelayer on the photosensitive layer. Optional additional layers containinganti-halation materials, adhesion promoters or release agents may alsobe used.

In the preferred embodiment, the substrate is composed of adimensionally and chemically stable base material which does notsignificantly change its size, shape or chemical properties as theresult of the heating coating or other treatments which it must undergo.One preferred material is polyethylene terephthalate. In the usual caseit has a thickness of from about 1 to about 10 mils, a more preferredthickness is from about 2-5 mils and most preferably from about 2-3mils. Suitable films include Hostaphan 3000, available from AmericanHoechst Corporation, Mylar D, available from DuPont and Melinex grades0; 052; 442; 516 and S, available from ICI. The surface of the substratemay be smooth or may be provided with a matte texture by various methodsknown in the art.

Matte films include Melinex 377 and 470 from ICI. These materials havethe unique property of giving the final image a desired matte finishwithout any extra steps. One can control the gloss of the final image byproperly selecting the matte finish of the temporary support. Thiseffect works because the top layer of the final image is originally incontact with this matte surface. This does not occur with a separaterelease layer between the temporary support and photosensitive layer. Anadditional advantage of coating on a matte surface is that subsequenttransferred layers generally adhere better to a rough surface than to asmooth surface.

A similar matte finish of the final image can be obtained by embossingthe shiny, top surface of the image with a matte material, such asdescribed above. This is done by laminating together the final image andmatte material under pressure and temperature. The matte material isthen generally removed after lamination. The advantage of this method isthat the finish of the final proof can be varied. Furthermore, thematting material can be used repeatedly.

A third method for producing a matte finish uses a heat transferablelayer, such as Butvar 90, available from Monsanto, coated onto a filmwith a rough surface, such as Melinex 329, available from ICI. Theadhesive layer is laminated to the final image under pressure andtemperature. Then the film with the rough surface is peeled off. Therough surface imparts a matte finish to the final image. The advantageis that all layers appear matte and that the extra adhesive layerprotects the image. U. S. Pat. Nos. 4,294,909 and 4,376,159, alsosuggests various methods for making a matte surface.

In either case, the substrate must have a release surface, that is, itmust be capable of releasably holding the photosensitive layer thereto.This may be accomplished either by the substrate surface beinginherently releasable, being rendered releasable by a suitable treatmentor being provided with a release layer over the substrate surface. Sucha release layer may comprise polyvinyl alcohol.

Releasably bonded to the release surface is the photosensitive layer.The photosensitive layer broadly comprises a photosensitizer, acolorant, a binding resin, and other optional ingredients such asplasticizers, acid stabilizers, surfactants, anti-static compositions,uv absorbers and residual coating solvents.

The photosensitizer is preferably a light sensitive, polymeric diazoniumsalt. The most preferred photosensitizer is the polycondensation productof 3-methoxy-4-diazo-diphenyl amine sulfate and 4,4'-bis-methoxymethyl-diphenyl ether, precipitated as mesitylene sulfonate as taught inU.S. Pat. No. 3,849,392. Other suitable photosensitizers are taught inU.S. Pat. No. 4,436,804. The diazo compounds of choice are preferablysoluble in organic solvents.

Suitable binding resins are substituted or unsubstituted acid containingacrylic copolymer having the formula ##STR2## wherein: R₁ is H, or CH₃

R₂ is CH₃, CH₂ CH₃, (CH₂)₃ CH₃, n-octyl, or 2-ethyl hexyl

R₃ is H, CH₃, or COOH

o is equal to 4 to 12, and

p is equal to 1, and

said copolymer having an average molecular weight in the range of fromabout 10,000 to about 300,000.

In this formula, the ratio of acid monomer portion to non-acid monomerpart is in the range of from about 1:4 to 1:12. This corresponds to anacid component in the range of from about 8% to about 20% of thecopolymer.

Polymer having such a structure include Elvacite (DuPont) 2013, 2014 and2028, Carboset (B. F. Goodrich) 514-A, 515, 525, 526, XL-27, and XL-44,Cyanamid CY-XC-4011, and Mocryl 151 (AO Polymer).

In the preferred embodiment the aforesaid copolymers have a molecularweight in the range of from about 25,000 to about 250,000 and morepreferably from about 150,000 to about 250,000.

Suitable polymers for modifying the acrylic-based color layer includestyrene-maleic anhydride polymers in both the half acid/half ester formand as the diacid such as Scripset (Monsanto) 520, 540, and 550 and SMA(Arco) 1440, 17352, and (Monsanto) B-72, B-79, and B-90 and polyvinylacetal/acetate/alcohol termpolymers such as those described in U.S. Pat.application Ser. No. 762,089 which is incorporated herein by reference.

These resins have the general formula

    -A-B-C

wherein a plurality of each of components A, B and C occur in an orderedor random sequence in the resin and wherein A is present in said resinat about 5% to about 20% by weight and comprises groups of the formula##STR3## B is present in said resin at about 4% to about 30% by weightand comprises groups of the formula ##STR4## and C is present in saidresin at about 50% to about 91% by weight; the weight amount ofcomponents A, B, and C being based on the total weight of the resin andcomprises acetal groups consisting of groups of the formulae ##STR5##where R is lower alkyl or hydrogen, and wherein said group I is presentin component C from about 75% to about 85%, group II is present incomponent C from about 3% to about 5%; and group III is present incomponent C from about 10% to about 22% the percent basis for the acetalgroups I, II, and III being on a mol basis of acetal groups I, II, andIII of component C and have a molecular weight of from about 5,000 toabout 100,000.

The colorants useful for the present invention include various classesof dyes and pigments. In the most preferred embodiment, pigments havingan average particle size of about 1 micrometer or less are used.

Optional plasticizers which may be incorporated into the photosensitivelayer include those of the phthalate and phosphate types. Preferredplasticizers include dibutyl phthalate and dimethyl phthalate. Acidstabilizers include phosphoric acid and p-toluene sulfonic acid.

These ingredients may be blended with such compatible solvents asethanol, methyl cellosolve and methyl ethyl ketone, coated on therelease surface, and dried. In the preferred embodiment, thephotosensitive layer has a coating weight between approximately 0.1 and5.0 g/m². The most preferred weight is from about 0.5 to 2.0 g/m².

In the preferred embodiment, the photosensitizer is present in thephotosensitive layer in an amount of from about 5 to about 40 percent byweight; or more preferably from about 10 to about 35 percent by weight.

In the preferred embodiment, the colorant is present in thephotosensitive layer in an amount of from about 10 to about 40 percentby weight; or more preferably from about 13 to about 34 percent byweight.

In the preferred embodiment, the binding resin is present in thephotosensitive layer in an amount of from about 25 to about 80 parts byweight; or more preferably from about 32 to about 75 parts by weight.

In the preferred embodiment, the ratio of the acrylic to the othermodifying polymers is from 5:1 to 1:2, more preferably from 3:1 to 1:1.

In the preferred embodiment, the plasticizer, when one is used, ispresent in the photosensitive layer in an amount of up to about 20 partsby weight; or more preferably up to about 15 parts by weight and mostpreferably from about 12 to about 15 parts by weight.

In the preferred embodiment, the acid stabilizer, when one is used, ispresent in the photosensitive layer in an amount of up to about 10 partsby weight.

Typical formulations for the photosensitive layer include:

    ______________________________________                                         I.          Yellow   Magenta   Cyan  Black                                   ______________________________________                                        methyl cellosolve                                                                          40       40        40    40                                      methyl ethyl ketone                                                                        40       40        40    40                                      tetrahydrofuran                                                                            10       10        10    10                                      Butyrolactone                                                                              5        5         5     4                                       Carboset XL-27                                                                             1        0.75      0.75  1                                       Elvacite 2014                                                                              0.5      0.25      0.25  --                                      Carboset 525 --       0.25      0.25  1.5                                     SMA 2625     0.5      0.75      0.75  0.5                                     Above diazo from                                                                           1.7      1.5       1.5   1.75                                    U.S. Pat. No. 3,849,392                                                       phthalo blue pigment                                                                       --       --        1     --                                      yellow pigment                                                                             1.3      --        --    --                                      magenta pigment                                                                            --       1         --    --                                      black pigment                                                                              --       --        --    1.25                                    optical density                                                                            0.9      1.3       1.2   1.6                                     ______________________________________                                    

    ______________________________________                                         II.         Yellow   Magenta   Cyan  Black                                   ______________________________________                                        methyl cellosolve                                                                          41       47.3      42    41.6                                    methyl ethyl ketone                                                                        42.6     47.8      41    41.6                                    Butyrolactone                                                                              10       --        10    10                                      Carboset XL-44                                                                             --       0.5       1     --                                      Carboset 525 2        1         1     1.9                                     Butvar B-90  1        0.25      0.5   --                                      Scripset 540 1        1         1.5   2                                       Above diazo from                                                                           1.35     0.7       1.3   2                                       U.S. Pat. No. 3,849,392                                                       phthalo blue pigment                                                                       --       --        1.7   --                                      yellow pigment                                                                             1.05     --        --    --                                      magenta pigment                                                                            --       1.45      --    --                                      black pigment                                                                              --       --        --    0.9                                     optical density                                                                            0.9      1.3       1.2   1.6                                     ______________________________________                                    

Scripset resins are available from Monsanto. SMA resins are availablefrom Arco. Carbosets are available from B. F. Goodrich. Elvacites areavailable from DuPont.

The adhesive layer comprises polyvinyl acetate and may optionallycontain such other desired components as uv absorbers, anti-staticcompositions and plasticizers. Useful polyvinyl acetates non-exclusivelyinclude Mowilith DM-6, 20, DM-22, 25, 30 and mixtures thereof, availablefrom Hoechst AG. These are usually dispersed in water, or dissolved inmethyl isobutyl ketone or n-butyl acetate or other solvent compositionsfor coating on the photosensitive layer. It is then dried to a coatingweight of from about 5 to about 30 g/m², more preferably from about 10to about 20 g/m². The layer may optionally contain a uv absorber such asUvinul D-50 from G.A.F. It may also contain a plasticizer such asResoflex R-296, available from Cambridge Industries. It may also containantistats, such as Gafac and Gafstat from G.A.F. It may also containother resins, such as Nitrocellulose RS 1/2, available from Hercules.The adhesive layer should not be tacky to the touch, during storage orduring development of the photosensitive element. The layer should havea softening point in the range of from about 60° C. to about 180° C.,preferably 60° C. to 120° C., more preferably 60° C. to 100° C. In thepreferred embodiment, the polyvinyl acetate is present in the adhesivelayer in an amount of greater than about 50 percent by weight. Theplasticizer may be present in an amount of up to about 30 percent byweight, the uv absorber up to about 20 percent by weight, and otherresins up to about 50 percent by weight.

Typical adhesive formulations include.

    ______________________________________                                        I.                                                                            Water            50.00                                                        Mowilith DM-22   50.00                                                        II.                                                                           n-butyl acetate  78.00                                                        Resoflex R-296   1.00                                                         Mowilith 30      21.00                                                        III.                                                                          n-butyl acetate  68.70                                                        Uvinul D-50      1.30                                                         Mowilith 20      30.00                                                        ______________________________________                                    

In operation, the photosensitive element is laminated to a receptorsheet via the adhesive layer. The receiver sheet should be resistant toany adverse effects which may be caused by the developer of choice. Forexample, the receiver sheet should be water resistant if aqueousdevelopers are used. Plastic or plastic coated receiver sheets areuseful for this purpose.

Useful receiver sheets include Melinex 329; 339; 994 and 3020 from ICI.Other white and non-white receiver sheets may also be used. Roughtextured and/or adhesion promoted surfaces are preferred for thereceiver, which must be able to withstand the laminating and developmentprocesses.

Lamination may be conducted by putting the receiver sheet in contactwith the adhesive side of the colored composite and then introducing thetwo materials into the nip of a pair of heated laminating rollers undersuitable pressure. Suitable laminating temperatures usually range fromabout 60° C. to about 90° C., preferably about 75° C. to about 85° C.After lamination, the substrate is peeled away, usually merely employingmanual peeling forces. The adhesive and photosensitive layers thusremain on the receiver sheet.

The photosensitive layer is imagewise exposed by means well known in theart either before or after lamination. Such exposure may be conducted byexposure to a uv light source through a photomask under vacuum frameconditions. Exposure may be performed with actinic light through aconventional negative flat. Exposures after lamination and peel apartare preferred for emulsion-to-emulsion contact. Mercury vapor dischargelamps are preferred over metal halide lamps. Filters may be used toreduce light scattering in the material.

After lamination, peel apart and exposure, the photosensitive layer isdeveloped by dissolving the non-exposed area in a suitable developer anddried. The adhesive layer is not removed by this development. Suitabledevelopers non-exclusively include:

    ______________________________________                                        I.                                                                            water              95.0                                                       sodium decyl sulphate                                                                            3.0                                                        disodium phosphate 1.5                                                        sodium metasilicate                                                                              0.5                                                        II.                                                                           water              89.264                                                     monosodium phosphate                                                                             0.269                                                      trisodium phosphate                                                                              2.230                                                      sodium tetradecyl sulfate                                                                        8.237                                                      ______________________________________                                    

Any developer solution which satisfactorily removes the non-exposedareas of the photosensitive layer after exposure while retaining theimage areas may be used. The selection of developer is well within theability of the skilled artisan.

The process can then be repeated whereby another photosensitive elementhaving a different color is laminated to the same receiver sheet overthe previously formed image. In the usual case, four colored layers areemployed to produce a full color reproduction of a desired image. Theseare cyan, magenta, yellow and black.

The following non-limiting example serves to illustrate the invention.

EXAMPLE I

Four photosensitive solutions of cyan, yellow, magenta, and black areproduced in accordance with the photosensitive formulations II describedabove. The pigment is introduced as a dispersion of propylene glycolmonomethyl ether, Carboset XL-44, and the appropriate pigment. Thesolutions are coated and dried separately to the required opticaldensity onto 3 mil Melinex 516 polyester film as a temporary support.The surface densities are roughly 1.3 g/m² for cyan, 0.9 g/m² foryellow, 1.2 g/m² for magenta, and 1.6 g/m² for black. The adhesivesolution, in particular adhesive formulation number II above, is coatedon top of the photosensitive layers and dried to an surface density of12 g/m². The yellow composite is then laminated at 80° C. with theadhesive side onto either side of a 7 mil Melinex 3020 polyesterreceiver sheet. The 516 temporary support is peeled away afterlamination, leaving the adhesive and photosensitive layers on thereceiver sheet. The yellow photosensitive layer is then exposed toactinic light through a photographic flat for the yellow color. Thereceiver sheet with the exposed yellow layer is then immersed for 15 secin developer II above at 27° C. with gentle pad rubbing on thephotosensitive side. The non-exposed, yellow areas are thereby washedoff and the exposed areas remain during development. The adhesive layeris not affected by the developer. After this treatment, the imagedmaterial is rinsed and then dried. The magenta composite is thenlaminated as before onto the imaged, yellow side of the receptor sheet.The temporary support is removed as before. The magenta layer is thenexposed through the magenta flat. It is then processed as with theyellow. The magenta is followed in a like manner by cyan and then byblack to give a four color image which is an accurate representation ofthe original from which separations are prepared.

Example II

Black coatings are made for comparison using the black formulas based onacrylic as well as a Black coating based entirely on Scripset 540polymer using the following formulations:

    ______________________________________                                                              BLACK    BLACK                                          MATERIAL              I        II                                             ______________________________________                                        methyl cellosolve     32       32                                             Dowanol PM            10       10                                             methyl ethyl ketone   41       41                                             butyrolactone         5        5                                              diacetone alcohol     5        5                                              dimethyl phthalate    --       1.0                                            Scripset 540          0.5      3.0                                            Carboset XL-44        1.0      --                                             Carboset 525          2.0      --                                             Butvar B-90           0.5      --                                             above diazo from U.S. Pat. No. 3,849,392                                                            2.0      2.0                                            Black pigment         1.0      1.0                                            ______________________________________                                    

The coatings are prepared in the method described in Example 1 and arelikewise overcoated, transferred, exposed, and developed. Uponlamination, an average of 2 to 4 pullout voids are observed in Black IIcoatings, as compared to an average of 0 to 1 pullouts in the Black I.The final exposed and developed images are stored at 50° C. and areobserved on a regular basis for signs of fracture. Black I imagessurvive such storage for two months; Black II images display fracturesin image areas in about 2 hours and show distortion of halftone dotsafter 18 hours, rendering the images useless for a graphic artsapplication.

What is claimed is:
 1. A method for forming a colored image whichcomprises(A) providing a photosensitive element which comprises, inorder:(i) a substrate having a release surface; and (ii) a singlephotosensitive layer on said release surface, which photosensitive layercomprises in admixture a light sensitive, negative working, polymericdiazonium compound in an amount sufficient to photosensitize the layer;a resinous binder composition in an amount sufficient to bind the layercomponents, which composition consists essentially of a major amount ofan acid containing acrylic copolymer having the formula ##STR6##wherein: R₁ is H or, CH₃ R₂ is CH₃, CH₂ CH₃, (CH₂)₃ CH₃, n-octyl, or2-ethyl hexyl R₃ is H, CH₃, or COOH o is equal to 4 to 12, and p isequal to 1, and said copolymer having an average molecular weight in therange of from about 10,000 to about 300,000, and at least one colorantin an amount sufficient to color the layer; and (iii) an adhesive layerdirectly adhered to said color photosensitive layer, which adhesivelayer comprises a polyvinyl acetate polymer and which adhesive layer hasa softening point in the range of from about 60° C. to about 180° C.;and thereafter (B) either(i) laminating said element with heat andpressure via said adhesive layer to a developer resistant receiversheet; and removing said substrate by the application of peeling forces;and imagewise exposing said photosensitive layer to actinic radiation;or (ii) imagewise exposing said photosensitive layer to actinicradiation; and laminating said element with heat and pressure via saidadhesive layer to a developer resistant receiver sheet; and removingsaid substrate by the application of peeling forces; or (iii) laminatingsaid element with heat and pressure via said adhesive layer to adeveloper resistant receiver sheet; and imagewise exposing saidphotosensitive layer to actinic radiation; and removing said substrateby the application of peeling forces; and (C) removing the non-exposedareas of said photosensitive layer with a liquid developer, whichremoving is conducted at a temperature at which said adhesive layer issubstantially non-tacky.
 2. The method of claim 1 wherein steps Athrough C are repeated at least once whereby another photosensitiveelement having at least one different colorant is laminated onto saidsheet over the non-removed portions of the previously laminatedphotosensitive layer or layers.
 3. The method of claim 1 wherein saidsubstrate comprises polyethylene terepthalate.
 4. The method of claim 1wherein said substrate has a matte surface.
 5. The method of claim 1wherein said release surface on said substrate comprises polyvinylalcohol.
 6. The method of claim 1 wherein said photosensitive layercomprises the polycondensation product of 3-methoxy-4-diazo-diphenylamine sulfate and 4,4'-bis-methoxy methyl-diphenyl ether precipitatedmesitylene sulfonate.
 7. The method of claim 1 wherein saidphotosensitive layer further comprises one or more ingredients selectedfrom the group consisting of plasticizers, acid stabilizers, antistaticcompositions, uv absorbers and surfactants.
 8. The method of claim 1wherein the coating weight of the photosensitive layer ranges from about0.1 to about 5.0 g/r.
 9. The method of claim 1 wherein thephotosensitizer is present in the photosensitive layer in an amount offrom about 5 to about 40 percent by weight.
 10. The method of claim 1wherein the pigment is present in he photosensitive layer in an amountof from about 10 to about 40 percent by weight.
 11. The method of claim1 wherein the binding resin is present in the photosensitive layer in anamount of from about 25 to about 80 percent by weight.
 12. The method ofclaim 7 wherein the plasticizer is present in the photosensitive layerin an amount of up to about 20 percent by weight.
 13. The method ofclaim 6 wherein the acid stabilizer is present in the photosensitivelayer in an amount of up to about 10 percent by weight.
 14. The methodof claim 1 wherein the adhesive layer has a coating weight of from about5 to about 30 g/m2
 15. The method of claim 1 wherein the adhesive layerfurther comprises one or more ingredients selected from the groupconsisting of uv absorbers, anti-static compositions, resins,nitrocellulose and plasticizers.
 16. The method of claim 1 wherein thepolyvinyl acetate is present in the adhesive layer in an amount of atleast about 50 percent by weight.
 17. The method of claim 15 wherein theuv absorber is present in the adhesive layer in an amount of up to about30 percent by weight.
 18. The method of claim 15 wherein the plasticizeris present in the adhesive layer in an amount of up to about 20 percentby weight.
 19. The method of claim 1 wherein the laminating step isconducted at a temperature of from about 60° C. to about 90° C.
 20. Themethod of claim 1 wherein said binder composition further comprises oneor more components selected from the group consisting of styrene maleicanhydride copolymers, polyvinyl acetals, and polyvinylacetal/acetate/alcohol terpolymers.